The report found that one in four children in the state start school with dental disease. Twenty-four percent of Hispanics and 23% of black children who are kindergarten age have untreated cavities, rates nearly twice that of whites, according to the report.

In addition, two-thirds of third grade children in low-income families have tooth decay, about two times the rate of tooth decay among children in families with higher incomes, the report found.

The overall rate of children in third grade with dental disease declined from 48% to 41% over the last four years, while the proportion of children with untreated dental disease dropped from 26% to 17%.

Alex White -- a dentist and director of analytics for the Catalyst Institute -- said that persistent dental disease among children is related to a lack of dental insurance, sugar-heavy diets and the absence of fluoride in water in some areas.

Fay Donohue, president and CEO of Delta Dental of Massachusetts, in a statement said, "This report provides compelling evidence that dental disease remains a serious problem for our children and especially among minority children and children from low-income families, even though dental disease is almost entirely preventable."

White added, "More needs to be done. We know we can make a difference; we're just not doing it for everyone" (Abel, Boston Globe, 1/24).